External HD with PS2

Sorry if this has been asked a trillion times before, but can I hook up an external hard drive to the kids ps2 via the USB port? If so, what software would I need to enable the ps to run the games from it?
Please go easy on me game dudes, I know fuck all about gaming. There - I said it.
:D

Anyone?

You Need A Mod Or Search google for a ps2 game backup

Thanks Neo.
Since posting the question, I've ordered a USBExtreme disc, Anyone have any experiences with this software?

I think the PS2 itself has a External HD, but I think it only works if u buy FF Online